Controlling apparatus.



` A. G. WESSLING.

. OONTBOLLING APPABATUS. urncuon Hun nsa. 9. 1901.

PatntedNov. 10, 1908.

50 i of either the speed or the load or both the UNI-TEE STATES ATENT OFFICE.

ALBERT G. wEssuNc, or NORWOOD, 01110, ASSIGNOR ro ALLIS-CHALMERS COMPANY, A CORPORATI'ON or NEW JERSEY, AND THE BULLOOK ELECTRIC MANUFACTURING com- 'PANY, A OORPORATION OF OHIO.

coN'moLLNG arraarus.

Specification of Letter' Patent.

Patented Nov. 10, 1908.

To ,all whom it may concern: g

Be it known that 1,. ALBERT G. WESSLING, citizen of the United States, residing at Norwood, in the countyof Hamilton and State of Ohio, have invented certain new and useful Improvements in Controllin Apparatus, of which the following is a full, c ear, and exact specification.

My invention relates to automatic stopping devices for power-driven machinery.

In operating many kinds of power-driven machincry, it is necessary g for the sake of safety that'` some means be provided for interruptin the supply of power When or before the 't of movement is reached. A number ofsuch schemes have been devised. So far as I am 'aware, however, they all have one common ob'ection. v On account of the momentum of t e moving parts the driven mechanism does not stop immediately upon interrupting the supply of power, but continues a short distance farther. The amount of such movement after the cessation of the supply of power depends upon the speed wit which the arts were moving and upon the load which t e, driven mechanism places upon the source of power. It is believed that none of the 'devices heretofore constructed for automatically interru ting the supply of owerjas the' driven mec amsm approaches ts limit of movement have taken into account the possible differences in'speed and in load, and so'all of them have generally either stopped the mechanism sooner than was necessary or have allowed it to overrun the desired sto ping point.

It is t e main object of my present invention to provide means matic stopping device'interru ts the suppl of wer to power-driven me'c ani'sm at suc a tme that the final sto ping of the mechanism takes place at the esired point regardless of its previous speed or the oad which it 1st put upon the source of power. With t object in view, I have provided means whereby the supply of power to powerdriven mechanism interrupted when such mechanism in its approach toward alimit of its 'movement has reached a point the distance of which froni such limit is a function speed and load of the driven mechanism.

whereby an auto- Considered somewhat more specifically my nventon provides n connection with driven mechanism, -such as an elevator, a hoist, or

.the like, and an electric motor for driving it, means whereby the suppl of current to the motor is shut off when t e driven mechanism is approaching a limit of its movement 4 and isat such momentum of the moving par s the driven mechanism will be carried just to .the predatermined limit of movement, whatever the speed and the load of such mechanism;

- The various novel'features of my invention drawin s and will be particular out in t e claims. r

Figure '1 shows somewhat .dia ammatically a hoisting apparatus .driven y' an electric motor and provi improved automatic stopp" e PP my device and Fig. 2 shows a modification of t e device" responsive to slpeed and load for controlling the point at w the motor is interrupted.

distance therefrom that by-,the

ed` with one form of a ch the supply of current to.

'65 will be apparent from the descrilption and' A winding drum 10 mounted on a shaft 11. l

in Fig. 1 represents. any form" of powerdriven mechanism, being here shown as a winding drum because m invention is :perhaps especially `applicab e chmery of various sorts. The shaft 11 and the parts carried thereby are driven by the electric motor 1'2, here shown as having 'a shunt field Winding 13, though obviously other forms of field widings may be used f desired. Shaft '11' carries two sets of fly' balls-14 and 15 and a'brake disk 16, the

brake 17 which coperates with the latter being normally spring-pressed into engage* ment with it but arranged to be disengaged by the electromagnet 18 in the armature crcuit of 11 are threaded and engage with nuts in slides 20 and 21, which thus move longitudinally of the shalt as .the shaft is rotated. The slides 20 and 22 and 23 respectivel the inner surfaces ofwhich are tapered. These tapered surfaces may be conical paraboloidal, or any other shape which is ound best in each articular case, bein' here shown as conic sake of simplicity. These intemally ta pered members 22 'and are spnng-pressed the motor 12. The ends of the *shaft 21 carry hollow members for the V so to hoistingmar i away from the slides and 21, but are drawn toward such slides by magnets 24 and respectively. These magnets are respectively in the armature circuit ofthe' motor and thus controlled by the* load on the motor when the flyballs and tapered members with which they are respectively associated As the shaft 11 tapered member 22 approach each other, and When it is* rotated In the other direction "the fly balls ,15 and tapered member 23'approach each other, the approaching parts engagin in either case at a time determined by the istention of the fly balls and the strength of current in the ma et 24 or 25.

The main switch and fie d Switch 29 being closed, the motor 12 can be started to drive the shaft in either direction by moving v the arm 31 is moved to the left.

the arm 31 of the controller 32 to ether side of its middle or ofi position. Assume that As scenesthe arm engages the various contact seg- V the bralredisk '16 to increase the rate of d-;

'broken, the

ments of the left hand side of the controller 32, the circuit of the motor armature 12 is completed from the left hand side of the switch 30, through the magnet 24, doublethrow solenoid Switch 33 in'its inner poitio the lower part of the arm 31, `magnet 18, ar-

mature 12, such part of the resistance 34 as is to the left of the arm 31, the upper, part of the arm 31, and' conductor 35' hand side of the Switch 30.

The brake 17 is lifted .by-the magnet 18, and the motor Will start and continue to drive the shaft 11 and the Winding drum 10 at a speed .determined by the osition of the arm 31 and in the direction .o the 'arrow at the left of said drum as lon as the arm 31 is in engagement With any of t e buttons of the resistance 34, unless the drum approaches a limit of its movement. In such case the tapered member 22 will'eng age with the fly calls 14 at a point determined by the speed of the 'shaft 11 and the strength of the armature current in the magnet 24. The greater the speed of the shaft 11 the sooner the en'- agement between the member 22 and the y balls 14, while the heavier the load on the motor 12 the later such engagementwill be. Upon 'such .engagement the circuit of solenoi 33' is 'closed, and such solenoid attracts j its core to'move the switch 33 into its outer position, thus breakin the circuit, including the motor armature, 't' e'ma et' 18, and the magnet 24, andtalso that of t opening magnet 33'. The motorarmature circuit; being power for the. slaft :1 l is cut ofl, while the nergization ofthe magnet 18 allowstheb'ake '17 togbe applied' to' .to the right crease 'n the speed .of the shaft 11.* The i v shape of the'internal surfaces of the member 22 and the strength ofthe of the fly.

the motor 12 are such that by breaking such I circuit at that point the drum 10 will be brought to rest when it has just reached its limit of travel As shown, the field circuit of the motor is only broken when the switch 29 is o ened.

e motor 12, having been thus stopped, can not be' started again by any movement of the arm 31 to the left of its middle position, for the circuit of the closing coil 33 of the Switch 33 can only be completed when' the arm 31 is moved to 'the right. When the arm 31 is so moved, the armature circuit of the motor is com leted in the op osite direc tion from the le f t hand side OF switch30, through the conductor 36, the' upper part of the arm 31, such part of the resistance 37 as is to the right of the arm 3.1, armature 12, .brake magnet 18, the lower art of the arm 31, double throw solenoid swtch 38 in its inner position, and magnet 25 to the right hand side of the Switch 30. As the motor 12 starts up to' drive the sha ft 11 in the direction'of the arrow at the ri ht' of the' drum 10, brake 17 bein`g`liftedduyr V ,the switch 33 is thrown intots; er osition, breaking ther circuit of its closing'coil As long as the arm 31 is to the right. of its middle position the motor 12 will continue to operate to drive the drum '10 'at a speed determined by the position of such arm, un-

33 in its movement.

less the drum reaches a oint the distance of j v the parts will carry the drum verse function of the loadon the motor 12 as r measured by the .current in the magnet 25. When such point-is reached 'the internally tapered member 23 engages the `fly balls 15 to complete; the circuit of the solenoid 38' to move the switch 38 to its outergosition,

ing the thus interrupti ng the circuit inclu .armature 12, magnet 18, and magnet also that of the openingsolenoid 38 fore, this interrupts the su the drum 10 and a 25, and f 'As bely o 'power to (FWS the brake 17 tobe set, bringing the-drum 10 to a stop at the proper pointj The motor dan not 'now :be started by an movement of arm 31 to the Light 'of its mi dle position, the' circuit of 'closing' solenoid' 38 of the double-throw Switch 38. beii ,completed only when. the arm 31 is move to the left. Upon such elo: sure ofthe switch 38 into its inner position the closing solenoid 38 is denergized. As long as the drum 10 does n'ot approach either .limit of its movement-the solenoids 33 and such which they may be placed.

38' are inactive, and the controller 32 controls the direction and the speed ofthe armature 12 in the usual manner.

The switchcs 33 and 38 are rovided with springs 33' and 38' respective y, which hold switches in either extreme position in It is 'impossible to complete the circuits of any of the actuatsolenoids of these switches unless such swtches are in positions from which they ma be'moved by such solenoids.

` A ith the arrangement shown in Fig. -1, the magnets 24 and 25 merely move the tapered members 22 and 23 longitudinally relatively to the slides 20 .and 21 res ectively. In some cases the arrangement 's own in Fig. 2 maig;l prove more desirable and accurate.

the arrangement of Fig; 2, the shaft 11, fFly balls 14, and slide 20 are the same as in g.' 1. Instead, however, of the internal cone 22, two hinged plates 22 are provided, these plates being arranged to bemoved in and out according as the current in the magnet 24% which is connected in the same manner as the magnet 24 in F ig. 1, decreases or increases. By' such' an *arrangement it is often ossible to obtain more accurate cutting o of the motor current at the proper oint. v

lVhile I have shown my invention as a plied where anautomatic stop is to be OE- tained only at the extreme limits of movement of the driven mciai i smit issalsoa 5 plicable where such aut'oatc' 'steps 'are to'. e obtained at intermediate-points,` as at the different floors'in an elevator system.

Many modifications in the precise arrangement here shown and described may be made without departing from the spirit and scope of my invention, and all such I aim to cover in the following claims.

What I claim as new isii 1.- In combination,' power-driven mechanism, and meansior intcrrupting the su ly of power to such mechanism when t e atter is approaching a predetermined stopping point and is at a distance therefrom which is a functionof the'speed ofthe driven mechanism; i

2. In combination, power-driven 'mechanism, and means for interrupting the suply of power to such mechanism when the atter is approaching a'limit of'i'ts travel and is at a distance therefrom' which 'is a function. of the power supplied to such driven mechamsm. v

' 3.' In combination, power-driven mechanism, and means for interrupting the su' ly of power to such mechanism when the atter is approaching a predetermined stoppoint and s at a distance therefrom whch is a function of the speed of the driven mechanism and of the load which such mech- 4 aninn places on its source of power. v

" 4. In combination, a, source' of power,

interrupting 'thes'upply of power by such rs at' a distance therefrom which is an inverse function of the load which such' mech anism places upon such 'source of power;

6. In combination, a source of 'power, mechanism driven thereby, 'and means for interrupting the su ply of power by such source to such meciianism when the latter is approaching a predetermined stopping point and is ata distance thererom wluch is anism and an iiverse` function of the power which is being supplied tosuch' mechanism bysuchsource of power.

7. In combination, an electric motor, for,

mechanism driven thereby and means interrupting the spply of current to the motor when such driven mechanism is at a is a function of its speed. n

8. In v combination, an electric' motor, mechanism driven thereby, and means for 'motor when such-drivenmechanism -is at a distance from a'lim'it of its movement Which is'a function V motor to -su'ch mechanism g 9. In combination, v an electric motor, mechanism driven thereby, and means for interrupting the supply of current to the motor when such driven mechanism is at a distance from 'a predetermined stopping point load on the motor.

10. 'In combination,' an electric motor, mechanism driven thereby, and means for interrupting the su ply of current to the mo- 'tor When such mecli -`its approa'ch to-a predetermined' stopping point the distance of which from such stoppin point is `a direct function of the speed of t e driven mechanism.

mechanism driven thereby, and means for interrupting the su ply of current to the motor when such mec anism reaches a point in its approach to a predetermined stopping point the distance of which from such stoppin point is an inverse function of the load on t e moton i 712. In combination, an electric jmotor, mechanism driven thereby, andmeans for interrupting the supply of current to the momechanism driven thereby, and means for.

distance from a limit of its movement which' of the power suppliedby such which is a function of its speed and ofthe source to such mechanism when the latteris s approaching a limit of its movement and 4 a direct functi'oniof the speed of such mech- 'interlupting the supply of current to the a anism reaches a point n n I 11. In combination, an electric motor, l

:its approach toa limit of its movement the distance of which from such limit of move-.1

ment is a direct functionof the speed of the driven mechanism and an 'inverse function of the power. supplied by such motor to such switches to sto the car automatically at top mechanism. V

. 1 3. In an electric elevator, provided with automatic .stop switches to'stop' the car at 'the elevator mechamsmand arran ed' to top and bottom landing, means aotuated by the elevator mechansm to cause these.

switches to'act earlier if the speed of the car v is high; than they will if the speed is low.

` .14. electric elevator provided with i 'switches to stop the car automatically at top 'and bottom of ts travel, a governor actuated r by the elevator mechanism, and arran ed to cause the switches to act earlier when t e car' speed is high, than when the car speed is low. 15. In an electric elevator rovided with 'automatic stop switches whic stop-the car A slowl.

7 and arranged to 'cause the switches to act` top andibottom landing, means for driving at predetermined points, means actuated by the elevator mechanism to cause these switches to'act earlier if the speed of the car is high than they will if the speed of the car earlier when the car speed is high than when the car speed is low. e

17. In .an electric ele'vator provided with automatic stop switches to stop the car at 'such load is the 'elevator, and means actuated by the' 'elevator mechanism for causing said stop switches to act later if the load on the drivi .means is heavy than they will if such load is ight.

18. In electric elevator provided with and bottom o its travel, means 'for driving said elevator, and a governor actuated by cause'- the switches to 'act later When t e load `on such drivin means is heavy than' when such load is li t. 19. In an e ectric elevator provided .with

stop switches to stop'the car at predeter- ,mined oints in its travel, means for driving l vator, and, means actuated by the elevator mechanism to cause said sto such e switches to 'act earlier ifthe load on suc driving mechanism is light than they will if heavy. f

20. In an electric elevator provided with switches to stop 'the car automatically at predetefmined points in its travel, means for such' elevator, and a governor actu-' atedc y the elevator'mechanism and arranged 'to cause the switches to act earlier when the load onsuch driving means is light than when such load is heavy.

'Intestimonywhere'ofI afiixmy signature,

in thepresence of two.,wit"nesses. ALBERT G., WESSLING. Witnesses: V A' GEo. B. SCHLEY,

FRED J. KrNsEY; 

